Phonological awareness and decoding are two significant predictors of reading comprehension proficiency. Evidence suggests that a deficiency in either skill can result in future reading problems, and children with reading disabilities constitute a significant proportion of individuals who are diagnosed as having a learning disability. Although previous investigations of the relations between phonological awareness and decoding exist, no investigation to date has examined the developmental relations between these skills using latent change score (LCS) modeling. LCS modeling provides a distinct advantage over other statistical models that are used to examine longitudinal change because LCS modeling allows for within-person developmental dynamic change to be explicitly modeled. Given this, LCS modeling provides a means for investigating leading and lagging indicators of change. We want to examine the developmental relations between phonological awareness and decoding ability in children who attended Head Start versus did not attend Head Start. We want to further examine the developmental relations between these skills in subgroups of readers who will be categorized using a known groups and an exploratory groups approach within latent class analysis. We will then compare the developmental relations of these skills for children with and without reading problems. The aim of this research is to further elucidate the co-developmental relations between phonological awareness and decoding so as to identify possible mechanisms of change for children who are experiencing reading difficulties, which are the primary goals of several federally-funded initiatives, such as No Child Left Behind and the National Center for Learning Disabilities. Aim 1. Examine the developmental relations between phonological awareness and decoding ability in two cohorts of children (Head Start versus non-Head Start) from ages 3 and 4 through first grade Aim 2. Examine whether the developmental relations between these skills vary based on reading ability by using LCS in conjunction with a known groups approach in latent class analysis Aim 3. Examine whether the developmental relations between these skills vary based on reading ability by using LCS in conjunction with an exploratory groups approach in latent class analysis